3. Many assume that they will be able to communicate with loved ones during a disaster, but often cell phone towers are damaged or so many people are trying to use the system that they network is overwhelmed. Plan in advance so that you are prepared for these contingencies.

B. Government Plan (Fig. 53-1)

C. Nongovernment Organizations

1. Ever since the anthrax attacks of 2000 and 2001, the destruction of the World Trade Center Towers on September 11, 2001, the SARS epidemic of 2004, and the continued devastation caused by nature (hurricanes, earthquakes, tornadoes, floods, and fires), The Joint Commission (TJC), the American Hospital Association, and state and county health departments have more closely monitored and evaluated hospitals’ and communities’ emergency preparedness.

FIGURE 53-1. The multiple issues for which the Federal Emergency Management Agency must prepare and with which agencies it must coordinate–the US Departments of Justice, Health and Human Services, Agriculture, Commerce, and Defense.

2. Despite the best effort of law enforcement, fire and rescue teams, and emergency medical agencies, hospitals will continue to play a vital role in helping communities respond to catastrophic events.

3. TJC has been proactive in recognizing the need for a “surge capacity” within health care systems to handle the large number of patients who might be victims of catastrophic events.

II. ROLE OF ANESTHESIOLOGIST IN MANAGEMENT OF MASS CASUALTIES

A. Anesthesiologists basic understanding of physiology and pharmacology, and their airway skills, fluid resuscitation expertise, and ability to manage ventilators and to provide anesthesia in the field environment, in the emergency department, in the operating room (OR), and in intensive care units (ICUs) will be invaluable.

B. During a mass casualty incident, an anesthesiologist may well be asked to provide anesthetic services in an area other than the OR or ICU.

C. Triage

1. If assigned to triage patients, the anesthesiologist will be expected to classify patients into four groups–those requiring immediate care, delayed care, first aid, and expectant (not expected to survive inadequate resources to adequately resuscitate without jeopardizing the lives of patients more likely to survive).

2. In the future, biotechnology may play a role, but at present, hospitals must rely on physicians’ experience

3. As emotionally difficult as the process might be of identifying or managing patients not expected to survive is the assessment of patients who may have been injured or been affected during a disaster but do not appear to require treatment but who might require delayed care (Table 53-2).

D. Decontamination

1. Decontamination is normally performed first and then patients are evaluated and triaged. (Clothes are removed, and individuals are washed with copious amounts of water, and if they have been exposed to a chemical agent a dilute solution of sodium hypochlorite, 0.5% [household bleach] can be used.)

2. If the patient presents with life-threatening injury (acute respiratory failure requiring emergency tracheal intubation), the patient is treated first and decontaminated afterward.

TABLE 53-2 EVALUATION OF PATIENTS WHO DO NOT REQUIRE IMMEDIATE TREATMENT BUT MAY REQUIRE DELAYED CARE

a. The intubation must be performed with the anesthesiologist wearing a hazard materials (HAZMAT) or a biohazard suit with multiple-layered gloves and a gas mask.

b. Consider securing the airway with a laryngeal mask airway, when indicated, rather than with a tracheal tube.

E. Emergency Department

1. Depending on the types of casualties but especially for casualties from a violent explosion, anesthesiologists might be assigned to manage patient’s airways and secure central venous access.

2. Anesthesiologists should position themselves at the head of the bed and assume responsibility for the airway and venous access.

3. If chemical weapons are also used, not only may tracheal intubation be required, but ventilator management may also be necessary.

III. CHEMICAL

A. Nerve Agents. Before the past century, it was unthinkable that rogue states or terrorists would use chemical agents. But today there is no doubt in anyone’s mind that chemical agents will be used again in the future. The nerve agents are so named because of their mechanisms of action.

1. Similar to organophosphate insecticides and the anticholinesterase drugs anesthesiologists use daily, nerve agents inhibit acetylcholinesterase at preganglionic muscarinic and postganglionic muscarinic and nicotinic receptors, leading to copious secretions, meiosis, arrhythmias, bronchospasm, tonic muscle contractions, respiratory paralysis, seizures, and death.

a. Similar to managing the side effects of neostigmine, a cholinergic agent and competitive muscarinic blockers (atropine or glycopyrrolate) is administered to attenuate and block the muscarinic side effects of the agents.

b. When anticipating a nerve agent attack, US military personnel pretreat themselves with low-dose pyridostigmine and don personal protective equipment (preventing the agent from contacting and wetting skin from, which it is readily absorbed.)

c. US military personnel carry syringes of atropine and pralidoxime chloride (2-PAM chloride), an oxime that reactivates acetylcholinesterase by removing the nerve agent from its binding site on the enzyme.

TABLE 53-3 DIAGNOSIS OF NERVE AGENT TOXICITY

2. Diagnosis (Table 53-3)

3. Treatment. The treatment for nerve agent poisoning is one with which every anesthesiologist is familiar.

a. Atropine (2–6 mg every 5–10 minutes until secretions begin to decrease) is a competitive muscarinic blocker.

b. Pralidoxime chloride is the better long-term treatment because it reactivates acetylcholinesterase by removing the organophosphate compound.

c. Depending on the extent of exposure, treatment is different. Patients with moderate (and severe) poisoning require treatment with atropine and 2-PAM chloride intramuscularly.

d. With nerve injury casualties, decontamination is critical. It needs to be done as quickly as possible, first by leaving the area of exposure. Patients are decontaminated by removing their clothing and washing with copious amounts of water in 5% hypochlorite (household bleach).

B. Pulmonary Agents

1. Chlorine and phosgene are the considered the classical pulmonary agents and the two most likely to be used by terrorists. If quantities are released that are sufficient to displace O₂, then death results from asphyxia. In addition, these two gases are extremely toxic to the lungs; individuals who survive the acute exposure who have inhaled even small amounts often develop acute lung injury or acute respiratory distress syndrome.

2. The treatment of the resulting noncardiogenic pulmonary edema from NO₂ or the pulmonary agents is supportive: mechanical ventilation using small tidal volumes (6–8 mL/kg), peak airway pressures <30 cm H₂O, and positive end-expiratory pressure and inspired oxygen concentrations of 50% to 60% or less.

C. Blood Agents

1. Cyanide inhibits cellular respiration by interrupting the oxidative electron transfer process in mitochondria.

2. The treatment for cyanide toxicity is similar to treatment of someone who had an accidental overdose of sodium nitroprusside (intravenous thiosulfate and supportive care, including tracheal intubation, ventilation with 100% oxygen, and inotropes and vasopressors to stabilize the cardiovascular system).

IV. BIOLOGIC (Table 53-4)

A. Smallpox

1. Terrorists might consider using smallpox as weapon because an increasing number of people no longer carry immunity.

2. An unvaccinated person develops a prodrome of malaise, headache, and backache with an onset of fever to as high as 40°C. The fever decreases over the next 3 or 4 days at which time a rash develops.

a. This progression is in contradistinction to chicken pox in which the rash develops at the same time as the fever.

b. Unlike chicken pox, smallpox has a predilection for the distal extremities and face, although no part of the body is spared. Also, all lesions in a patient with smallpox are at the same stage, but with chicken pox, lesions are at multiple different stages, including papules, vesicles, pustules, and scabs.

TABLE 53-4 BIOLOGIC AGENTS USED FOR WARFARE